Epic Code LAB2111082 Glucose Tolerance, 1 hour test, 50 g (Gestational Diabetes Screen)
Test Name Alias
Glucose 1 hr Post 50 g | Glucose Tolerance | Glucose | GTT | OGTT | 8040
Interface Order Alias
10146
Ordering Instructions
This test is recommended and only available as a screen for PREGNANT PATIENTS at 24-28 weeks gestation.
For safety and accuracy of testing, patients are encouraged to have Oral Glucose Tolerance Tests (OGTT) performed at one of our Outpatient Service Centers.
GlucoCrushTM, the glucola drink used in Spectrum Health Grand Rapids Laboratory does not contain gluten.
Specimen Requirements
Specimen Collection: Blood
Container(s): 4.5 mL Mint Green Top (Lithium Heparin Gel) or 5.0 mL Gold Top (Serum Separator-SST Gel)
Preferred Volume to Collect: 4.5 mL
Minimum Volume to Collect: 1.0 mL
Capillary collect ok? Yes
Microtainer acceptable: Yes
Collection Instructions:
- Avoid hemolysis
- After collection, gently invert tube 8-10 times.
- Specimen should be processed within 2 hours – See Processing Instructions.
Processing Instructions (Laboratory, Outpatient or Off-site collection)
- Processed Specimen: Plasma or Serum
- Centrifuge/Spin: Yes
- Aliquot: Yes
- Processes Minimum Volume: 0.5 mL Plasma or Serum
- Processing Instructions:
- Plasma is preferred specimen type
- Green Tube/Plasma: Centrifuge within 1 hour after collection.
- Gold Tube/Serum: Allow blood to clot for 30 minutes in a vertical position and centrifuge within 2 hours.
- Minimum plasma/serum volume: 0.5 mL
- Transport Temperature: Refrigerated
GlucoCrushTM, the glucola drink used in Spectrum Health Grand Rapids Laboratory does not contain gluten.
Specimen Stability
Ambient: 8 hours
Refrigerate: 72 hours
Frozen: aliquot plasma/serum for longer storage
Laboratory Retention: 72 hours
Test Frequency
Available daily, usual TAT 1 day.
Reference Range
Female
65 – 135 mg/dL
Performing Department
Chemistry
Performing Department Laboratory Location
Corewell Health Reference Laboratory, Grand Rapids, MI
Corewell Health Big Rapids Laboratory, Big Rapids, MI
Corewell Health Blodgett Laboratory, Grand Rapids, MI
Corewell Health Gerber Laboratory, Fremont, MI
Corewell Health Kelsey Laboratory, Lakeview, MI
Corewell Health Ludington Laboratory, Ludington, MI
Corewell Health Pennock Laboratory, Hastings, MI
Corewell Health Reed City Laboratory, Reed City, MI
Corewell Health Greenville Laboratory, Greenville, MI
Corewell Health Zeeland Laboratory, Zeeland, MI
Methodology
Enzymatic
CPT
82950, 82950
CDM Code
3018295001, 3018295001
Epic Test ID
1230100719
LOINC
Glucose 1Hr PP: 1504-0
Reviewed Date
3/7/2024